81337530 has 32 divisors (see below), whose sum is σ = 195955200. Its totient is φ = 21607232.

The previous prime is 81337523. The next prime is 81337559. The reversal of 81337530 is 3573318.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3031 + ... + 13109.

It is an arithmetic number, because the mean of its divisors is an integer number (6123600).

Almost surely, 2^81337530 is an apocalyptic number.

81337530 is an abundant number, since it is smaller than the sum of its proper divisors (114617670).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81337530 is a wasteful number, since it uses less digits than its factorization.

81337530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10358.

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 81337530 is about 9018.7321725396. The cubic root of 81337530 is about 433.2750289735.

The spelling of 81337530 in words is "eighty-one million, three hundred thirty-seven thousand, five hundred thirty".